The objectives are to conduct immunologic, clinical, biochemical, and metabolic multidisciplinary studies of trophoblastic diseases. Our ability to establish tissue culture cell lines of hydatid mole and choriocarcinoma makes the immunologic and biochemical studies possible: to elucidate the role of HL-A and ABO histocompatibility antigens, and their corresponding immune responses, as factors in the development, progression and outcome of choriocarcinoma; to study biochemically the roles of nuclear proteins in the regulation of gene expression. Clinical investigations include (1) early detection of choriocarcinoma associated with term gestation and with abortion, (2) early detection of invasive mole and of choriocarcinoma associated with hydatid mole, (3) developing procedures for the determination at an early time the effectiveness or lack of effectiveness of a chemotherapeutic agent(s), and (4) development of chemotherapeutic regimen for patients with choriocarcinoma at "high risk". The effect of malignancy (choriocarcinoma) and of a non-malignant trophoblastic disease (invasive mole) on carbohydrate metabolism will be studied. Consultation and education will continue to be important elements of the activities.